However, the 29-year-old said he's slowly ramping up his activity now that he's made the trip ahead of the season's return.
"I just had two practices so I have to talk with strength coach, (Suns coach Monty Williams), and the whole team," Rubio said, according to ESPN's Andrew Lopez. "I feel good but we have to be smart about it. It's a preseason game. We have to figure out a plan that's day by day."
Rubio has averaged 13.1 points, 8.9 assists, 3.9 rebounds, and 1.5 steals per game during his 57 starting appearances this season.
When asked for a specific timeline of his diagnosis, Baynes indicated it had been at least a month.
"I haven't touched a basketball in 30 days," he said. "It's been a long time since being first found to be positive. The results take a little while."
Baynes added: "I'm in that protocol where I have the antibodies that we've tested. I have the antibodies. I'm not contagious, but I still need those negatives (tests) because, at the end of the day, that's the criteria the NBA has set up."
The 33-year-old was in the midst of his best pro season to date before the league suspended its schedule in March. Baynes averaged 11.5 points, 5.6 rebounds, and 1.6 assists in just over 22 minutes per game while starting 28 of his 42 appearances in 2019-20.
Phoenix is slated to face the Washington Wizards on July 31 in its first outing of the eight-game seeding phase.